Animals take in oxygen gas from the air and use it for respiration. Mammal(including humans) and birdsuse lungs. These must stay moist so that gases can dissolve and pass easily into or out of the blood. Fish use gills and many very small animals. Frogs use their whole body surface to obtain and realease gas es.Like animals, plants take in oxygen for respiration. Plants must also take in carbon dioxide for the plant building activity of photosynthesis. Plants use their leaves to obtain the gases they need from the air. Leaves have special holes in them called stomata that allows gases to pass in and out. Just like lungs, the inside of the leaf has to remain damp so that the gases can desolve and move around.
These are some pictures that might help you with the topic and some others.
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Trees take in oxygen in the morning at give oxygen at night.
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Birds and mammals use their lungs to take in oxygen and gases.
These are some pictures that might help you with the topic and some others.